San Antonio Mayor Julian Castro will deliver the keynote address on the opening night of the Democratic National Convention, making him the first Latino to receive that assignment.

Castro will share the Sept. 4 speaking duties in Charlotte, N.C., with first lady Michelle Obama. President Bill Clinton and Massachusetts Senate candidate Elizabeth Warren will speak Wednesday night, followed on Thursday by Vice President Joseph Biden and President Barack Obama.

Castro's prominent role, announced today by the the convention committee, is the latest evidence that Castro and his twin brother, state Rep. Joaquin Castro, are rising stars in the Democratic Party.

Joaquin Castro, who is running to replace retiring Rep. Charlie Gonzalez (D-Texas), did not face a runoff today and is likely headed to Congress next year.

"Having both the First Lady and Mayor Castro speak on the opening night of our convention will bring together two incredible leaders whose life stories both embody the promise of America, that if you work hard and play by the rules, you can make it," said Los Angeles Mayor Antonio Villaraigosa, the convention chairman.